"In the shot in which Alfred Hitchcock's cameo occurs, the music briefly changes to "Funeral March of a Marionette" by Charles Gounod, which is best known as the main theme for Alfred Hitchcock Presents."

That well-known dum-de-duh-duh-de-dum-de-duh was just inserted into the background music, which was a Strauss waltz. Lorna's answer is correct.

What role has been played by Charlton Heston, Peter Vaughan, Wallace Beery, Vic Tayback, Orson Welles, Tim Curry, Jack Palance, and many others (including one so closely identified with the role that I left him out)?

Long John Silver. The omitted actor also portrayed a famous real life pirate whose museum I visited recently in North Carolina...What was his real name and the one by which he is best known, and what did he call his ship?